The same has held true for UC Berkeley's peregrine falcons Annie and Grinnel, under the care of the Cal Falcons research team.
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Annie and Grinnell have lived on top of UC Berkeley's Campanile since 2016, but late last month Annie suddenly flew the coop.
After several years of keeping watch atop the Cal campus, suddenly Annie disappeared. Experts fear she was hurt, dead or abandoned her territory.
But then several days later, Annie returned.
"I was sitting there working on my computer, and then I look at the camera and I see a bird sitting where Annie usually likes to perch," said Sean Peterson, Ph.D., a Cal Falcons ornithologist. "It was unmistakably her. And I let off some expletives".
So were the theories correct? Where did Annie really fly off to?
Well, you'll just have to click the video player above to watch the full interview with Dr. Peterson, and be sure to tune into ABC7 News' new digital streaming show, ABC7@7, broadcast every day at 7 a.m.
If you're on the ABC7 News app, click here to watch live